This invention relates to internal combustion engines and more particularly to a new fuel-saving and pollution-reducing system, wherein controlled quantities of water are added to the usual hydrocarbon fuel in a novel and highly effective manner.
The problems of operating internal combustion engines efficiently throughout the wide range of speeds and loads to which they are subjected in automotive use has been present throughout the history of the inception and development of gasoline engine driven vehicles, and many expedients have been employed or attempted to solve these problems. At small loads the air throttle valve of the engine carburetor, which controls engine load, is in a nearly closed position, and the cylinders of the engine accordingly receive a small amount of air-fuel mixture and thus, the engine operates at a relatively low pressure and consequently at low thermodynamic efficiency. Operation under these conditions also produces maximum air-pollution. The net result is that present day internal combustion engines operate at relatively high efficiency only when the throttle is at, or near its full-open position. If the compression ratio of the engine is increased, it improves this inefficient small load operation, as well as the efficiency of the whole operation, but this introduces the problem of knocking at higher operating loads.
It has been known for many years that adding water to the air-fuel mixture of an internal combustion engine allows an increase in compression ratio without knocking and thus improves the overall efficiency. However, general use of this expedient has not been practical for a number of reasons, one of which is the lack of automatically controlling the amount of water introduced to the fuel system with respect to the quantity of liquid fuel being introduced. Among even greater problems may be mentioned the fact that the water thus introduced must be at least partially distilled water, with no solid ingredients, which is not always available, and with all prior systems this approach has required a water tank in addition to the usual fuel tank. Such systems also present a freezing problem with respect to the supply of the water in the water tank and the water delivery conduit.